This invention relates to an image recording and playback apparatus and method and a recording medium, and more particularly to an image recording and playback apparatus and method and a recording medium by which a representative picture to be used for specification of contents of moving pictures can be searched out and displayed.
In recent years, increase in capacity and reduction in cost of recording media such as a hard disk and increase in speed of processing of compression coding of a moving picture signal and a sound signal (hereinafter referred to collectively as AV signal) have been and are proceeding. Thus, electronic apparatus have been developed which make use of various techniques to compress and encode, record and then play back an AV signal of a television program.
An electronic apparatus of the type mentioned allows recording of a plurality of AV signals of different television programs onto a recording medium of a large capacity represented by a hard disk. Therefore, in order to make it possible for a user to manage a plurality of recorded AV signals of different programs readily, the electronic apparatus preferably has a function of extracting and recording a still picture (representative picture) from an image signal of a program being recorded.
For example, an electronic apparatus which has a function of producing and displaying a representative picture for each title (program) records time information such as a time stamp (recording hour) or a frame number of each frame onto a hard disk together with time information of the representative picture. Then, when an instruction to display a representative picture is issued from the user, the electronic apparatus accesses the hard disk to search for the representative picture from a time stamp recorded in advance on the hard disk and causes a monitor to display the representative picture. Consequently, the user can grasp contents of the title from the displayed representative picture or select a desired title or scene from among a plurality of titles.
However, in order for such an electronic apparatus as described above to search for a representative picture, a comparison table for contrast between time stamps and recorded positions (addresses) on the hard disk, that is, a table which is referred to to discriminate at which address of the hard disk a representative picture is recorded, must be produced.
Further, even if such a comparison table as described above is produced, the electronic apparatus cannot search out a desired representative picture rapidly.